pratt



(No ModeL) v N.W. PRATT. HAND HOLE PLATE. No. 565,604; Patented Aug. 11,1896.-

mlmaoogzo amvmto'o @51 aiifowm )7. Jaw-4....

UNITED STATES PATENT OFFICE.

NAT WV. PRATT, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE BABOOCK & WILOOXCOMPANY, OF NEW YORK, N. Y.

HAN D-HOLE PLATE.

SPECIFICATION forming part Of Letters Patent No. 565,504, dated August11, 1896.

Application filed November 23, 1895. Serial No. 569,896. (No model.)

- York, have invented a new and useful Improvement in Hand-Hole Plates,of which the following is a specification.

In the handling of finished hand-hole plates for steam-generators, 850.,both before application and during temporary removals of such plates,when they are constructed as usual with the hole-seat and nut-seat atright angles to. the adjoining exterior or slantheight surface,considerable trouble has been experienced from damage to such seats orfaces by the dropping of the plates and the striking of the same on theedges of the seats, thereby raising a portion of the seats and requiringthe same to be refaced.

The object of the invention is to avoid the liability to such damage, asfar as possible, by so constructing the plate as to protect such seats.

In the accompanying drawings, Figure 1 represents in partial side viewand in partial section a hand-hole plate embodying the invention. Fig. 2shows a rear view of the same. Fig. 3 represents in partial side Viewand in partial section, on a smaller scale, a handhole plate of thecommon form, on which portions of the seats have been upset or raised,due to droppings or falls of the plate.

In the common form of plate (shown in Fig. 3) the exterior orslant-height surface s joins the hand-hole seat or face A of the plate,as well as the nut seat or face B thereof, at substantially rightangles, so that sharp edges 15 t are present all around said seats.Experience has shown that where such plates are accidentally dropped orfall, they not infrequently strike on one of such edges, particularly onthat surrounding the seat A, thereby denting the edge and raising orupsetting a portion of the seat, as indicated at 00. Before the platecan be applied, therefore, the affected seat must be refaced or dressedoff, in order that a steam-tight fit may be had on the seat A, oraproper fit for the nut on the face B.

In my improved form of plate (shown in Figs. land 2) the 01d sharp edgessurrounding the seats are done away with by generously beveling theedges, as at a and I), respectively. It has been found that, byconstructing the plates as described, the liability of an injury to theseats A and B is very largely avoided, and that the plates when droppedwillalmost always strike on the edge 0 and the seats A and B beundisturbed by the fall. In fact nearly the whole surfaces of the bevelsa and I) act as protections to the respective seats, so that the latterare rarely injured, and about all the time and expense heretoforerequired to reface the seats is saved. The improved plate, therefore, isgreatly superior to the old form, and is no more expensive tomanufacture.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. As an improved article of manufacture, a hand-hole plate having itshole seat or face surrounded by a beveled portion extending outwardlyfrom said seat, substantially as set forth.

2. The improved hand-hole plate herein described having its hole seat orface and its nut seat or face respectively surrounded by beveledportions extending outwardly from said seats, substantially as setforth.

NAT W. PRATT.

Witnesses:

CHAS. W. FORBES, GHAs. HAUSMANN.

